Display panel and driving circuit thereof

ABSTRACT

A driving circuit for a display panel is disclosed. The driving circuit includes at least a driving signal line connected to a display driving signal transmission unit delivering display driving signal produced by the display driving signal transmission unit to sub-pixels of the display panel through the driving signal line; and a number of data signal lines connected to a display data provision unit delivering display data signal produced by the display data provision unit to the sub-pixels. For each subset of the sub-pixels that are of a same component color, at least two data signal lines, starting from different points of time, deliver display data signal to the subset of sub-pixels that are of the same component color. The driving circuit effectively resolves glitches to input signal resulted from heavy transient load to the input signal.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present disclosure relates to display technologies, and inparticular to a driving circuit for a display panel.

2. The Related Arts

The demand for liquid crystal display (LCD) is continuously increasing,and people are asking for even greater resolution and better displayquality. Therefore, how to improve LCD display quality becomes a majorissue.

Existing LCDs are internally structurally as shown in FIG. 1, where adriving circuit for multiple sub-pixels of different component colors ina row of pixel units is depicted. The pixel units are denoted asS(1)˜S(2N), and each pixel unit includes three sub-pixels of threecomponent colors. The sub-pixel of component color red is denoted as R,the sub-pixel of component color green is denoted as G, and thesub-pixel of component color blue is denoted as B. GATE(N) is thedriving signal line providing driving signals for the sub-pixels in arow of pixel units. MUXR, MUXG, and MUXB are data signal lines providingdata signals for R, G, and B sub-pixels, respectively. For existingmultiplexer (MUX) driving structure, there are 1:2 MUX (2:4 MUX) type or1:3 MUX (2:6 MUX) type. The driving structure shown in FIG. 1 is 1:3 MUXtype.

Existing LCDs work as follows. When driving signal line GATE(N) israised from low-level to high-level and as such provides voltage to thegates of MOS transistors connected to GATE(N). The MOS transistors areconducted and, after a preset period T1, the data signal line MUXR israised to high level. Then, all thin film transistors (TFTs) that areconnected to the R sub-pixels in a row of pixel units are conducted(i.e., T01, T04, T07, and T10 in FIG. 1 are conducted simultaneously),and all R sub-pixels corresponding to the row actuated by GATE(N) arecharged. In other words, data signal line MUXR provides data signals toall R sub-pixels in a row of pixel units.

Similarly, after charging to all R sub-pixels corresponding to the rowactuated by GATE(N) are done, data signal line MUXR is lowered to lowlevel. After a preset period T2, the data signal line MUXG is raised tohigh level. Then, all TFTs that are connected to the G sub-pixels in arow of pixel units are conducted (i.e., T02, T05, T08, and T11 in FIG. 1are conducted simultaneously), and all G sub-pixels corresponding to therow actuated by GATE(N) are charged.

After charging to all G sub-pixels corresponding to the row actuated byGATE(N) are done, data signal line MUXG is lowered to low level. After apreset period T3, the data signal line MUXB is raised to high level.Then, all TFTs that are connected to the B sub-pixels in a row of pixelunits are conducted (i.e., T03, T06, T09, and T12 in FIG. 1 areconducted simultaneously), and all B sub-pixels corresponding to the rowactuated by GATE(N) are charged.

After charging to all B sub-pixels corresponding to the row actuated byGATE(N) are done, data signal line MUXB is lowered to low level. After apreset period T4, the driving signal line GATE(N) is lowered to lowlevel, and the cycle of a row's charging is completed. Repeating theabove process then can complete the entire LCD's charging.

FIG. 2 is a timing sequence diagram showing the driving signal lineGATE(N), data signal lines MUXR, MUXG, and MUXB of the LCD of FIG. 1. Asillustrated, during a high-level cycle of GATE(N), MUXR, MUXG, and MUXBsequentially charge sub-pixels of corresponding component colors,respectively.

FIG. 3 is a waveform diagram showing the actual waveforms of the drivingsignal line GATE(N), data signal lines MUXR, MUXG, and MUXB of the LCDof FIG. 1. As illustrated, when the data signal line MUXR (or MUXG, orMUXB) starts charging sub-pixels of corresponding component color,liquid crystal module (LCM) instantaneously becomes a greater loading tothe driving IC of the LCD. As such, glitches as shown in FIG. 3 appearin the output of the driving IC, i.e., the actual input signal to MOStransistors (Gate driver On Array, GOA). The actual input signal can bethe clock (CK) signal, a frame start signal (STV), RESET signal, etc.

SUMMARY OF THE INVENTION

Therefore, the present disclosure teaches a driving circuit for adisplay panel that resolves the problem of glitches appearing in theactual input signal of GOA when data signal lines of the display panelcharge sub-pixels of different component colors.

The display panel includes a number of pixel units arranged in a pixelunit array. Each pixel unit includes a number of sub-pixels of differentcomponent colors. The driving circuit includes, for the sub-pixels in arow of pixel units, at least a driving signal line connected to adisplay driving signal transmission unit delivering display drivingsignal produced by the display driving signal transmission unit to thesub-pixels through the driving signal line, and a number of data signallines connected to a display data provision unit delivering display datasignal produced by the display data provision unit to the sub-pixels.For each subset of the sub-pixels that are of a same component color, atleast two data signal lines, starting from different points of time,deliver display data signal to the subset of sub-pixels that are of thesame component color.

Specifically, each subset of the sub-pixels that are of a same componentcolor are divided into at least two groups of sub-pixels. The number ofdata signal lines is identical to the number of groups divided. Each ofthe at least two data signal lines delivers display data signal to oneof the at least two groups of sub-pixels.

Specifically, the at least two data signal lines delivers display datasignal to the at least two groups of sub-pixels starting at respectivepoints of time with a preset gap therebetween.

Specifically, the at least two data. signal lines delivers display datasignal to the at least two groups of sub-pixels with respective andoverlapped charging periods.

Specifically, the data signal lines deliver display data signal tosubsets of the sub-pixels that are of different component colors withrespective and non-overlapped charging periods.

The driving circuit resolves glitches resulted from heavy transient loadto input signal, thereby enhancing the quality of the input signal andthe display quality as well.

The above driving method conducts contact detection while displayingimages so that, within a display scan cycle, the times for image displayand for contact detection, respectively, are not shortened. As such, theimage display and contact detection performances of an Incell LCD panelare both guaranteed.

BRIEF DESCRIPTION OF THE DRAWINGS

To make the technical solution of the embodiments according to thepresent disclosure, a brief description of the drawings that arenecessary for the illustration of the embodiments will be given asfollows. Apparently, the drawings described below show only exampleembodiments of the present disclosure and for those having ordinaryskills in the art, other drawings may be easily obtained from thesedrawings without paying any creative effort. In the drawings:

FIG. 1 is a schematic diagram showing a driving circuit for multiplesub-pixels of different component colors in a row of pixel units of anexisting LCD;

FIG. 2 is a timing sequence diagram showing the driving signal lineGATE(N), data signal lines MUXR, MUXG, and MUXB of the driving circuitof FIG. 1;

FIG. 3 is a waveform diagram showing the actual waveforms of the drivingsignal line GATE(N), data signal lines MUXR, MUXG, and MUXB of thedriving circuit of FIG. 1;

FIG. 4 is a schematic diagram showing a driving circuit for thesub-pixels of different component colors in a row of pixel units of adisplay panel according to an embodiment of the present disclosure;

FIG. 5 is a timing sequence diagram showing the driving signal lineGATE(N), data signal lines MUXR, MUXG, MUXG(N), MUXB, MUXB(N) of thedriving circuit of FIG. 4; and

FIG. 6 is a waveform diagram showing the actual waveforms of the drivingsignal line GATE(N), data signal lines MUXR, MUXR(N), MUXG, MUXG(N),MUXB, MUXB(N) of the driving circuit of FIG. 4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present disclosure teaches a driving method for display panels thatinclude a pixel unit array having multiple pixel units arranged in anarray. Each pixel unit includes sub-pixels of different componentcolors.

For the sub-pixels in a row of pixel units of the display panel, thedriving circuit includes at least a driving signal line connected to adisplay driving signal transmission unit which delivers the displaydriving signal produced by the display driving signal transmission unitto the sub-pixels through the driving signal line. The driving circuitalso includes multiple data signal lines connected to a display dataprovision unit which delivers display data produced by the display datasignal produced by the display data provision unit to the sub-pixelsthrough the data signal lines. At least two of the data signal lines arefor the sub-pixels of a same component color. The two data signal linesdelivers display data signal to the sub-pixels of the same componentcolor starting from different points of time.

By using at least two data signal lines to deliver display data signalto the sub-pixels of the same component color in a row of pixel unitscan effectively reduce the transient load of data signal lines whencharging the sub-pixels of each component color, thereby avoiding theglitches in the input signal.

Assuming that each pixel unit include a sub-pixel R of component colorred, a sub-pixel G of component color green, and a sub-pixel B ofcomponent color blue, FIG. 4 is a schematic diagram showing a drivingcircuit for the sub-pixels of different component colors in a row ofpixel units of a display panel according to an embodiment of the presentdisclosure.

As illustrated, the driving circuit is of the 1:3 MUX type. The row ofpixel units are denoted as S(1)˜S(2N), GATE(N) is the driving signalline providing driving signals for the sub-pixels in the row of pixelunits, and MUXR, MUXR(N), MUXG, MUXG(N), MUXB, MUXB(N) are data signallines. providing data signals for R, G, and B sub-pixels, respectively.MUXR and MUXR(N) are data signal lines for all R sub-pixels in the rowof pixel units. That is, MUXR and MUXR(N) jointly charge all Rsub-pixels in the row of pixel units. MUXG and MUXG(N) are data signallines for all G sub-pixels in the row of pixel units. That is, MUXG andMUXG(N) jointly charge all G sub-pixels in the row of pixel units. MUXBand MUXB(N) are data signal lines for all B sub-pixels in the row ofpixel units. That is, MUXB and MUXB(N) jointly charge all B sub-pixelsin the row of pixel units.

As illustrated in FIG. 4, the sub-pixels of a same component color inthe row of pixel units are divided into at least two groups where agroup of sub-pixels are serviced by one of the data signal lines. Thenumber of data signal lines is therefore identical to the number ofgroups divided.

As illustrated, R sub-pixels are divided into two groups: a first groupincluding those denoted as T01 and T07, and a second group denoted asT04 and T10. Data signal line MUXR charges the second group ofsub-pixels T04 and T10, and data signal line MUXR(N) charges the firstgroup of sub-pixels T01 and T07.

Similarly, G sub-pixels are divided into two groups: a third groupincluding those denoted as T02 and T08, and a fourth group denoted asT05 and T11. Data signal line MUXG charges the fourth group ofsub-pixels T05 and T11, and data signal line MUXG(N) charges the thirdgroup of sub-pixels T02 and T08.

Similarly, B sub-pixels are divided into two groups: a fifth groupincluding those denoted as T03 and T09, and a sixth group denoted as T06and T12. Data signal line MUXB charges the sixth group of sub-pixels T06and T12, and data signal line MUXB(N) charges the fifth group ofsub-pixels T03 and T09.

The data signal lines MUXR, MUXR(N), MUXG, MUXG(N), MUXB, MUXB(N) chargethe corresponding sub-pixels as follows.

When driving signal line GATE(N) is raised from low-level to high-leveland as such provides voltage to the gates of MOS transistors connectedto GATE(N). The MOS transistors are conducted and, after a preset periodT1, the data signal line MUXR is raised to high level. Then, all thinfilm transistors (TFTs) that are connected to the R sub-pixels of thesecond group in the row of pixel units are conducted (i.e., T04 and T10in FIG. 4 are conducted simultaneously), and these R sub-pixels arecharged. In other words, data signal line MUXR provides data signals toall R sub-pixels of the second group in the row of pixel units.

After a preset period ΔT, the data signal line MUXR(N) is raised to highlevel. Then, all thin film transistors (TFTs) that are connected to theR sub-pixels of the first group in the row of pixel units are conducted(i.e., T01 and 107 in FIG. 4 are conducted simultaneously), and these Rsub-pixels are charged. In other words, data signal line MUXR(N)provides data signals to all R sub-pixels of the first group in the rowof pixel units. The preset period ΔT is determined according to thedriving capability of the driving IC, the resistance, capacitance,impedance of the display panel, and the dielectric coefficient of thedisplay panel's material.

It should be noted that the division of sub-pixels of a same componentcolors are not limited to two groups only. Alternative embodiments ofthe present disclosure may divide the sub-pixels of a same componentcolor into three or more than three groups. The number of data signallines is therefore increased correspondingly. In these embodiments, eachdata signal lines charge respective groups of sub-pixels sequentiallywith preset time gaps, until all sub-pixels of the same component colorin the row specified by GATE(N) are charged.

After all R sub-pixels in the row specified by GATE(N) are charged, datasignal lines MUXR and MUXR(N) are reduced to low level. After a presetperiod Δt, the data signal line MUXG is raised to high level. Then, allthin film transistors (TFTs) that are connected to the G sub-pixels ofthe fourth group in the row of pixel units are conducted (i.e., T08 andT11 in FIG. 4 are conducted simultaneously), and these G sub-pixels arecharged.

After the preset period ΔT, the data signal line MUXG(N) is raised tohigh level. Then, all thin film transistors (TFTs) that are connected tothe G sub-pixels of the third group in the row of pixel units areconducted (i.e., T02 and T05 in FIG. 4 are conducted simultaneously),and these G sub-pixels are charged.

It should be noted that the division of G sub-pixels are not limited totwo groups only. Alternative embodiments of the present disclosure maydivide the G sub-pixels into three or more than three groups. The numberof data signal lines is therefore increased correspondingly. In theseembodiments, each data signal lines charge respective groups of Gsub-pixels sequentially with preset time gaps, until all G sub-pixels inthe row specified by GATE(N) are charged.

After all G sub-pixels in the row specified by GATE(N) are charged, datasignal lines MUXG and MUXG(N) are reduced to low level. After a presetperiod Δt, the data signal line MUXB is raised to high level. Then, allthin film transistors (TFTs) that are connected to the B sub-pixels ofthe sixth group in the row of pixel units are conducted (i.e., T09 andT12 in FIG. 4 are conducted simultaneously), and these B sub-pixels arecharged.

After the preset period ΔT, the data signal lute MUXB(N) is raised tohigh level. Then, all thin film transistors (TFTs) that are connected tothe B sub-pixels of the fifth group in the row of pixel units areconducted (i.e., T03 and T06 in FIG. 4 are conducted simultaneously),and these B sub-pixels are charged.

It should be noted that the division of B sub-pixels are not limited totwo groups only. Alternative embodiments of the present disclosure maydivide the B sub-pixels into three or more than three groups. The numberof data signal lines is therefore increased correspondingly. In theseembodiments, each data signal lines charge respective groups of Bsub-pixels sequentially with preset time gaps, until all B sub-pixels inthe row specified by GATE(N) are charged.

After all B sub-pixels in the row specified by GATE(N) are charged, datasignal lines MUXB and MUXB(N) are reduced to low level. After a presetperiod Δt, the driving signal line GATE(N) is lowered to low level, andthe cycle of a row's charging is completed. Repeating the above processthen can complete the entire display panel's charging.

It should be noted that what is shown in FIG. 4 is only exemplary and aperson of the related art may adjust the driving circuit structure shownin FIG. 4 according to his requirement. For example, the number ofdriving signal line may be increased and two or more driving signallines are employed to deliver display driving signals to the sub-pixelsof multiple component colors in a row of pixel units of the displaypanel. Or the number of data signal lines may be increased and three ormore data signal lines are employed to deliver display data signals tothe sub-pixels of a same component color. In addition, a person of therelated art may adjust the order of data signal lines' chargingsub-pixels according to his requirement. Therefore, solutions employingat least two data signal lines to charge sub-pixels of a same componentcolor should all fall within the scope of the present disclosure. Forsimplicity's sakes, these solutions are detailed here.

FIG. 5 is a timing sequence diagram showing the driving signal lineGATE(N), data signal lines MUXR, MUXR(N), MUXG, MUXB(N), MUXB, MUXB(N)of the driving circuit of FIG. 4.

As illustrated, during a high-level cycle of GATE(N), MUXR, MUXR(N),MUXG, MUXG(N), MUXB, MUXB(N) sequentially charge sub-pixels ofcorresponding component colors, respectively, starting from differentpoints of time

To charge the two groups of sub-pixels of a same component color, thetwo corresponding data signal lines have their charging periodsoverlapped. In FIG. 5, T denotes a charging period to a group ofsub-pixels. It can be seen that the charging periods of MUXR and MUXR(N)are overlapped but their starting times are separated by a preset gap.Similarly, the charging periods of MUXG and MUXG(N) are overlapped buttheir starting times are separated by a preset gap, and the chargingperiods of MUXB and MUXB(N) are overlapped but their starting times areseparated by a preset gap. By having at least two data signal lines tocharge a group of sub-pixels of a same component color, respectively,with different starting times, the transient load, by becomingtime-shared load, to the input signal is effectively reduced.

However, as shown in FIG. 5, the charging periods of data signal linesto sub-pixels of different component colors are not overlapped. That is,the charging periods of MUXR and MUXR(N), the charging periods of MUXGand MUXG(N), and the charging periods of MUXB and MUXB(N) are notoverlapped with each other.

FIG. 6 is a waveform diagram showing the actual waveforms of the drivingcircuit of FIG. 4.

In contrast to what is shown in FIG. 1 where glitches appear in theinput signal when, in a row of pixel units, all sub-pixels of componentcolor red share a single data signal line MUXR, all sub-pixels ofcomponent color green share a single data signal line MUXG, and allsub-pixels of component color blue share a single data signal line MUXB,FIG. 6 shows that the present disclosure effectively resolves glitchesresulted from heavy transient load to input signal, thereby enhancingthe quality of the input signal and the display quality as well.

Embodiments of the present disclosure have been described, but notintending to impose any unduly constraint to the appended claims. Anymodification of equivalent structure or equivalent process madeaccording to the disclosure and drawings of the present disclosure, orany application thereof, directly or indirectly, to other related fieldsof technique, is considered encompassed in the scope of protectiondefined by the clams of the present disclosure.

What is claimed is:
 1. A driving circuit for a display panel, thedisplay panel comprising a plurality of pixel units arranged in a pixelunit array, each pixel unit comprising a plurality of sub-pixels ofdifferent component colors, the driving circuit comprising, for thesub-pixels in a row of pixel units: at least a driving signal lineconnected to a display driving signal transmission unit deliveringdisplay driving signal produced by the display driving signaltransmission unit to the sub-pixels through the driving signal line; anda plurality of data signal lines connected to a display data provisionunit delivering display data signal produced by the display dataprovision unit to the sub-pixels; wherein, for each subset of thesub-pixels that are of a same component color, at least two data signallines, starting from different points of time, deliver display datasignal to the subset of sub-pixels that are of the same component color.2. The driving circuit as claimed in claim 1, wherein each subset of thesub-pixels that are of a same component color are divided into at leasttwo groups of sub-pixels; the number of data signal lines is identicalto the number of groups divided; and each of the at least two datasignal lines delivers display data signal to one of the at least twogroups of sub-pixels.
 3. The driving circuit as claimed in claim 2,wherein the at least two data signal lines delivers display data signalto the at least two groups of sub-pixels starting at respective pointsof time with a preset gap therebetween.
 4. The driving circuit asclaimed in claim 3, wherein the at least two data signal lines deliversdisplay data signal to the at least two groups of sub-pixels withrespective and overlapped charging periods.
 5. The driving circuit asclaimed in claim 1, wherein the data signal lines deliver display datasignal to subsets of the sub-pixels that are of different componentcolors with respective and non-overlapped charging periods.
 6. A displaypanel comprising a plurality of pixel units arranged in a pixel unitarray, each pixel unit comprising a plurality of sub-pixels of differentcomponent colors; and a driving circuit wherein the driving unitcomprises, for the sub-pixels in a row of pixel units, at least adriving signal line connected to a display driving signal transmissionunit delivering display driving signal produced by the display drivingsignal transmission unit to the sub-pixels through the driving signalline, and a plurality of data signal lines connected to a display dataprovision unit delivering display data signal produced by the displaydata provision unit to the sub-pixels; for each subset of the sub-pixelsthat are of a same component color, at least two data signal lines,starting from different points of time, deliver display data signal tothe subset of sub-pixels that are of the same component color.
 7. Thedisplay panel as claimed in claim 6, wherein each subset of thesub-pixels that are of a same component color are divided into at leasttwo groups of sub-pixels; the number of data signal lines is identicalto the number of groups divided; and each of the at least two datasignal lines delivers display data signal to one of the at least twogroups of sub-pixels.
 8. The display panel as claimed in claim 7,wherein the at least two data signal lines delivers display data signalto the at least two groups of sub-pixels starting at respective pointsof time with a preset gap therebetween.
 9. The display panel as claimedin claim 8, wherein the at least two data signal lines delivers displaydata signal to the at least two groups of sub-pixels with respective andoverlapped charging periods.
 10. The display panel as claimed in claim6, wherein the data signal lines deliver display data signal to subsetsof the sub-pixels that are of different component colors with respectiveand non-overlapped charging periods.